From: Ingo Molnar Date: Fri, 23 Nov 2012 18:19:07 +0000 (+0100) Subject: x86/boot: Add CONFIG_PARAVIRT_SPINLOCKS quirk to arch/x86/boot/compressed/misc.h X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=927392d73a97d8d235bb65400e2e3c7f0bec2b6f;p=linux-beck.git x86/boot: Add CONFIG_PARAVIRT_SPINLOCKS quirk to arch/x86/boot/compressed/misc.h Linus reported the following new warning on x86 allmodconfig with GCC 5.1: > ./arch/x86/include/asm/spinlock.h: In function ‘arch_spin_lock’: > ./arch/x86/include/asm/spinlock.h:119:3: warning: implicit declaration > of function ‘__ticket_lock_spinning’ [-Wimplicit-function-declaration] > __ticket_lock_spinning(lock, inc.tail); > ^ This warning triggers because of these hacks in misc.h: /* * we have to be careful, because no indirections are allowed here, and * paravirt_ops is a kind of one. As it will only run in baremetal anyway, * we just keep it from happening */ #undef CONFIG_PARAVIRT #undef CONFIG_KASAN But these hacks were not updated when CONFIG_PARAVIRT_SPINLOCKS was added, and eventually (with the introduction of queued paravirt spinlocks in recent kernels) this created an invalid Kconfig combination and broke the build. So add a CONFIG_PARAVIRT_SPINLOCKS #undef line as well. Also remove the _ASM_X86_DESC_H quirk: that undocumented quirk was originally added ages ago, in: 099e1377269a ("x86: use ELF format in compressed images.") and I went back to that kernel (and fixed up the main Makefile which didn't build anymore) and checked what failure it avoided: it avoided an include file dependencies related build failure related to our old x86-platforms code. That old code is long gone, the header dependencies got cleaned up, and the build does not fail anymore with the totality of asm/desc.h included - so remove the quirk. Reported-by: Linus Torvalds Cc: "H. Peter Anvin" Cc: Thomas Gleixner Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar --- diff --git a/arch/x86/boot/compressed/misc.h b/arch/x86/boot/compressed/misc.h index 89dd0d78013a..805d25ca5f1d 100644 --- a/arch/x86/boot/compressed/misc.h +++ b/arch/x86/boot/compressed/misc.h @@ -2,15 +2,14 @@ #define BOOT_COMPRESSED_MISC_H /* - * we have to be careful, because no indirections are allowed here, and - * paravirt_ops is a kind of one. As it will only run in baremetal anyway, - * we just keep it from happening + * Special hack: we have to be careful, because no indirections are allowed here, + * and paravirt_ops is a kind of one. As it will only run in baremetal anyway, + * we just keep it from happening. (This list needs to be extended when new + * paravirt and debugging variants are added.) */ #undef CONFIG_PARAVIRT +#undef CONFIG_PARAVIRT_SPINLOCKS #undef CONFIG_KASAN -#ifdef CONFIG_X86_32 -#define _ASM_X86_DESC_H 1 -#endif #include #include